Progress in the determination of Mellin moments of the pion LCDA using the HOPE method

TL;DR

This paper advances the calculation of the pion's light-cone distribution amplitude by determining its second and fourth Mellin moments using the HOPE method, contributing to non-perturbative QCD insights.

Contribution

It introduces a new application of the heavy-quark operator product expansion to compute Mellin moments of the pion LCDA.

Findings

Second Mellin moment: 0.210 ± 0.013 (stat.) ± 0.034 (sys.)

Results agree with previous determinations

Demonstrates the effectiveness of the HOPE method for non-perturbative QCD calculations

Abstract

The pion light-cone distribution amplitude (LCDA) is a central non-perturbative object of interest for the calculation of high-energy exclusive processes in quantum chromodynamics. In this article, we discuss the calculation of the second and fourth Mellin moment of the pion LCDA using a heavy-quark operator product expansion. The resulting value for the second Mellin moment is $ \langle{ \xi^2 }\rangle(\mu = 2~\text{GeV})= 0.210 \pm 0.013\text{ (stat.)} \pm 0.034\text{ (sys.)}$. This result is compatible with those from previous determinations of this quantity.